LAUSR

Objectives To compare the percentage of voids in matched-taper single-cone fillings with GuttaFlow Bioseal or BioRoot RCS root canal sealers, using micro-computed tomography. Materials and methods Forty-eight single-rooted mandibular premolars were prepared using rotary files and randomly allocated into 2 groups ( n  = 24), wherein the canals were filled with a matched-taper single gutta-percha cone and one of the two sealers: Group 1, GuttaFlow Bioseal and Group 2, BioRoot RCS. The specimens were scanned with micro-CT before and after root canal filling. A specialized software was used to calculate the voids volume percentage (V%) in the filling for the whole root canal, root canal thirds, and the last millimeter from the apex. Data were statistically analyzed by ANOVA and Tukey tests ( p  < 0.05). Results Root canals filled with GuttaFlow Bioseal had significantly less V% than those filled with BioRoot RCS in all the root-thirds ( p  < 0.05) except at the apical 1 mm ( p  > 0.05). Comparing the root-thirds, GuttaFlow Bioseal showed similar V% in all regions ( p  > 0.05), while BioRoot RCS group had significantly greater V% in the coronal third compared with the other thirds ( p  < 0.05). Conclusions Root canals filled with a matched-taper single cone and GuttaFlow Bioseal had significant less voids than those with BioRoot RCS, except at the apical 1 mm. Clinical relevance Voids in root fillings have been reported to have a negative impact on root canal treatment. This study highlights the percentage of voids in root fillings composed of a single cone of gutta-percha with two types of calcium silicate–based bioceramic sealers.